Method Of Making A Golf Ball With Lattice Reinforced Layer

ABSTRACT

Methods of making a golf ball that includes a lattice reinforced layer, which is a layer made of at least two materials with different properties, includes various injection and compression molding steps. In some embodiments, the lattice reinforced layer is manufactured using a shutoff molding technique so that the entire lattice reinforced layer is molded in the same mold. In other embodiments, a grid for the lattice layer is formed first, then filled using an injection molding technique.

BACKGROUND

The present invention relates generally to a golf ball having a layermade of interdigitated materials and methods of making such a layer.

The game of golf is an increasingly popular sport at both amateur andprofessional levels. A wide range of technologies related to themanufacture and design of golf balls are known in the art. Suchtechnologies have resulted in golf balls with a variety of playcharacteristics and durability. For example, some golf balls have abetter flight performance than other golf balls. Some golf balls with agood flight performance do not have a good feel when hit with a golfclub. Some golf balls with good performance and feel lack durability.Thus, it would be advantageous to make a durable golf ball with a goodflight performance that also has a good feel.

SUMMARY

Methods of making a golf ball that includes a lattice reinforced layeras any layer of a multi-layer golf ball is disclosed. In broad terms,the lattice reinforced layer is a layer made of at least two materialswith different properties. The materials are interdigitated with eachother, where one material forms a grid with pores while the othermaterial protrudes through the pores. In some embodiments, the latticereinforced layer is manufactured using a shutoff molding technique sothat the entire lattice reinforced layer is molded in the same mold. Inother embodiments, the grid is formed first using cutting andcompression molding techniques, then the grid is overmolded with thesecond material to fill in the pores of the grid.

In one aspect the invention provides a method of making a golf ball, themethod comprising the steps of: providing a mold having a cavity, a moldsurface, and telescoping members; positioning the telescoping members inan extended position, so that the telescoping members are in contactwith the mold surface; injecting a first material into the cavity;ceasing injecting the first material into the cavity; moving thetelescoping members to a retracted position; and injecting a secondmaterial into the cavity to produce a lattice portion.

A method of making a golf ball comprising the steps of: making a core;making a grid from a first material, the first material having at leastone pore; forming the grid into a cup; positioning the cup on the core;and overmolding a second material onto the grid, so that the secondmaterial at least partially fills the at least one pore of the grid.

In another aspect, the invention provides a method of making a golfball, the method comprising: providing a mold having a first mold halfhaving a cavity and a first mold surface, and a second mold half havinga second mold surface and elongated members extending away from thesecond mold surface; closing the mold so that the elongated members arein contact with the mold surface and a first gap is formed between thefirst mold surface and the second mold surface; injecting a firstmaterial into the first gap so that the first material flows around theelongated members to leave at least one opening in a first molded part;replacing the second mold half with a third mold half while leaving thefirst molded part in the first mold, the third mold half having a thirdmold surface; closing the mold so that a second gap is formed betweenthe first molded part and the third mold surface; and injecting a secondmaterial into the second gap so that the second material flows into thesecond gap and the at least one opening in the first molded part to forma lattice layer.

Other systems, methods, features and advantages of the invention willbe, or will become, apparent to one of ordinary skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be included within this description and this summary, bewithin the scope of the invention, and be protected by the followingclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereference numerals designate corresponding parts throughout thedifferent views.

FIG. 1 is a schematic drawing of a two-piece golf ball;

FIG. 2 is a schematic drawing of a three-piece golf ball, the golf ballhaving a core, a mantle, and a cover;

FIG. 3 is a schematic drawing of a three-piece golf ball, the golf ballhaving an inner core, an outer core, and a cover;

FIG. 4 is a schematic drawing of a four-piece golf ball;

FIG. 5 is an isometric drawing of a golf ball, with the cover partiallypeeled away to reveal a lattice layer;

FIG. 6 is an enlarged, partial, cross-sectional view of a lattice layer;

FIG. 7 is a close-up view of a portion of FIG. 6;

FIG. 8 is an exploded view of the portion of the lattice layer shown inFIG. 6;

FIG. 9 is a schematic drawing of a mold configured to make ahemispherical lattice layer using a shutoff molding technique, showingtelescoping members in a retracted position and the mold open;

FIG. 10 is a schematic drawing of the mold shown in FIG. 9, showing thetelescoping members in a retracted position and the mold closed;

FIG. 11 is a schematic drawing of the mold shown in FIG. 9, showing thetelescoping members in an extended position and the mold closed;

FIG. 12 is a schematic drawing of the mold shown in FIG. 9, with onehalf of the mold replaced with a mold containing no telescopingportions, and the mold is in a closed position;

FIG. 13 is a schematic drawing of an alternate embodiment of a method ofmanufacturing a golf ball with a lattice layer, showing a die cutter anda portion of material being cut to form a grid;

FIG. 14 is a schematic drawing of a mold configured to mold the gridshown in FIG. 13 into a substantially hemispherical cup, with the gridinserted in position and the mold open;

FIG. 15 shows the mold of FIG. 14 in a closed position, with the gridconformed to the mold surfaces of the mold;

FIG. 16 shows the hemispherical cups positioned to receive apreviously-molded component of the golf ball, prior to being joinedtogether to form a gridded component;

FIG. 17 shows the gridded component in a completed configuration, withthe hemispherical cups joined together and trimmed at the seamline;

FIG. 18 shows the gridded component positioned in a mold configured toreceive material via an injection molding process;

FIG. 19 shows a completed golf ball, with a portion of the golf balllifted away to show the lattice layer.

DETAILED DESCRIPTION

Generally, the present disclosure relates to a golf ball with a latticereinforced layer. In broad terms, the lattice reinforced layer is alayer made of at least two materials with different properties. Thematerials are interlocked with each other, where one material forms agrid with pores while the other material protrudes through the pores. Insome embodiments, the lattice reinforced layer is manufactured using ashutoff molding technique so that the entire lattice reinforced layer ismolded in the same mold.

The golf ball may be made by any suitable process. The process of makingthe golf ball may be selected based on a variety of factors. Forexample, the process of making the golf ball may be selected based onthe type of materials used and/or the number of layers included.Exemplary processes are discussed below with respect to the individuallayers of the exemplary embodiment.

As used herein, the term “about” is intended to allow for engineeringand manufacturing tolerances, which may vary depending upon the type ofmaterial and manufacturing process, but which are generally understoodby those in the art. Also, as used herein, unless otherwise stated,compression, hardness, COR, and flexural modulus are measured asfollows:

Compression deformation: The compression deformation herein indicatesthe deformation amount of the ball under a force; specifically, when theforce is increased to become 130 kg from 10 kg, the deformation amountof the ball under the force of 130 kg subtracts the deformation amountof the ball under the force of 10 kg to become the compressiondeformation value of the ball. All of the tests herein are performedusing a compression testing machine available from Automated DesignCorp. in Illinois, USA. The ADC compression tester can be set to apply afirst load and obtain a first deformation amount, and then, after aselected period, apply a second, typically higher load and determine asecond deformation amount. Thus, the first load herein is 10 kg, thesecond load herein is 130 kg, and the compression deformation is thedifference between the second deformation and the first deformation.Herein, this distance is reported in millimeters. The compression can bereported as a distance, or as an equivalent to other deformationmeasurement techniques, such as Atti compression.

Hardness: Hardness of golf ball layer is measured generally inaccordance with ASTM D-2240, but measured on the land area of a curvedsurface of a molded ball. Other types of hardness, such as Shore C orJIS-C hardnesses may be provided as specified herein. For materialhardness, it is measured in accordance with ASTM D-2240 (on a plaque).

Method of measuring COR: A golf ball for test is fired by an air cannonat an initial velocity of 131 ft/s, and a speed monitoring device islocated over a distance of 0.6 to 0.9 meters from the cannon. Whenstriking a steel plate positioned about 1.2 meters away from the aircannon, the golf ball rebounds through the speed-monitoring device. Thereturn velocity divided by the initial velocity is the COR. A CORmeasuring system is available from ADC.

The construction of a golf ball made according to the present method isnot limited to the embodiments mentioned with specificity herein. Forexample, a golf ball in accordance with this disclosure may generallytake any construction, such as a conforming or non-conformingconstruction. Conforming golf balls are golf balls which meet the Rulesof Golf as approved by the United States Golf Association (USGA).

Thus, the disclosure herein can be applied to any of the ballsillustrated in FIGS. 1-4. For example, FIG. 1 shows a golf ball 100having a two-piece construction comprising core 120 and cover layer 110.FIG. 2 shows a second golf ball 200 having a three-piece constructioncomprising core 230, mantle layer 220, and an outer cover layer 210.FIG. 3 shows a third golf ball 300 having a three-piece constructioncomprising inner core layer 330, an outer core layer 320, and outercover layer 310. FIG. 4 shows a fourth golf ball 400 having inner corelayer 440, outer core layer 430, mantle layer 420, and outer cover layer410. Typically, each layer essentially encompasses interior layers.

The disclosure thus encompasses these golf balls, and golf balls having5 or more layers or pieces. However, for convenience herein, thedisclosure will be directed to the four embodiments shown in FIGS. 2-4,though it is anticipated that the lattice reinforced layer may be anylayer from the innermost or center core to and including the cover.

FIG. 5 shows a golf ball 500 including a lattice layer 520. In thisembodiment, lattice layer 520 is positioned adjacent a cover layer 510.Cover layer 510 may be any type of cover layer known in the art, such asan ionomer, urethane, or rubber layer with dimples provided foraerodynamic effects.

Lattice layer 520 is generally formed from two materials interlocked orinterdigitated with each other. A first material forms a first latticeportion 522, while a second material forms a second lattice portion 524.The materials are different, so it is intended that first latticeportion 522 and second lattice portion 524 have different properties andcharacteristics. For example, a monolithic layer formed from a singlematerial has a single response to impacts, deformation, and compressiveforces, such as are typically experienced by a golf ball when struck bya golf club. However, in a layer such as lattice layer 520, the responseprofile is more complex, as the different materials have differentresponses to the same imparted force. This complex response profilegives a golf ball designer a greater ability to fine tune theperformance of a golf ball than when the golf ball designer is using asingle material to make a monolithic layer.

For example, the first material of first lattice portion 522 may have afirst strength, such as yield strength, failure strength, and tensilestrength, a first hardness, a first compression, and a first toughness.The second material of second lattice portion 524 may have a secondstrength, such as yield strength, failure strength, and tensilestrength, a second hardness, a second compression, and a secondtoughness. One or more of these and other characteristics can vary byonly a small amount between the first material of first lattice portion522 and the second material of second lattice portion 524 or one or moreof these and other characteristics can vary by a large amount betweenthe first material and the second material.

For example, the hardness may vary between the first material of firstlattice portion 522 and the second material of second lattice portion524. In an example where lattice layer 520 is a mantle layer, such asmantle layer 220 of FIG. 2 or mantle layer 420 of FIG. 4, the firstmaterial may have a relatively high hardness, for example, greater than65 Shore D. A high hardness mantle may be beneficial if the cover layeris relatively soft, so that driver distance and spin are optimized.However, a high hardness mantle may have too hard a feel for somegolfers. Therefore, the second material may have a lower hardness, forexample, less than 60, to give the golf ball a softer feel. In someembodiments, the second material of second lattice portion 524 may be anionomer with a Shore D hardness of 55 and the first material of firstlattice portion 520 may have a Shore D hardness of 65. This relationshipmay be reversed (i.e., first lattice portion 520 may have a Shore Dhardness of 55 and second lattice portion 524 may have a Shore Dhardness of 65), depending on the desired feel and/or the type of playerusing the golf ball. Some examples of combinations of materials, whereone material is used in first lattice portion 520 and the other materialis used in second lattice portion 524, include terpolymer ionomer as thesofter material and copolymer ionomer as the harder material; polyamidecopolymer ionomer blend as the harder material and polyamide elastomerterpolymer ionomer blend as the softer material. In general, polyamideionomer blends of different hardnesses may be used in the lattice layer.Other benefits of varying hardness in the cover layer can be found in USPatent Publication Number 2011/0177884, the disclosure of which isincorporated herein by reference.

The configuration of the lattice may also affect the response to impact.As shown, first lattice portion 522 forms a grid or net-like structurewhich contains openings, holes, or pores. Though shown as a regular gridwith evenly spaced openings, first lattice portion 522 may have anyconfiguration, such as irregularly-spaced openings, randomly-spacedopenings, or the like. If first lattice portion 522 were a monolithicmaterial, first lattice portion 522 could be relatively stiff. However,forming the openings in first lattice portion 522 lowers the stiffnessof first lattice portion 522 over a monolithic layer of the samethickness. If second material of second lattice portion 524 is amaterial with a lower stiffness than that of first material, then theoverall stiffness of the layer. This lower stiffness may also soften thefeel of the ball for some golfers.

FIG. 6 shows a portion of lattice layer 520 to show one embodiment ofthe lattice structure. First lattice portion 522 defines the openingsfilled by second lattice portion 524. In this embodiment, the openingsare generally square in cross-sectional shape. The width 534 of a squarecross-sectional shaped second lattice portion 524 within the opening maybe any width desired, ranging from a relatively small percentage of thesurface area of lattice layer 520 to roughly half of the surface area oflattice layer 520 or greater. In some embodiments, for example, width534 may range from 0.5 mm to 10 mm. In other embodiments, width 534 maybe larger or smaller than this range.

The distance between two adjacent openings is defined by first distance530 and second distance 532. First distance 530 and second distance maybe substantially the same, to provide a fairly regular grid, or mayvary. In some embodiments, first distance 530 and/or second distance 532may vary along the length or width of a single opening, such as when theopening itself does not have a regular polygonal shape, for example,then the opening is generally circular or oval.

In some embodiments, as shown most clearly in FIG. 6, lattice layer 520is constructed to have a continuous, smooth interdigitated surface 527formed from the interlocked members of first lattice portion 522 andsecond lattice portion 524, and a second surface 523 formed entirely ofthe second material of second lattice portion 524. Smooth interdigitatedsurface 527, where neither lattice portion extends beyond the other,allows neither lattice portion to dominate the response on impact. Thissmooth surface can be achieved using a shutoff molding techniquedescribed below. This configuration is shown in greater detail in FIG.7.

FIG. 7 shows the interface of first lattice portion 522 and secondlattice portion 524. As can be clearly seen, the top interface 542between first lattice portion 522 and second lattice portion 524 showsthat first lattice portion top surface 536 is coextensive with secondlattice portion top surface 538. FIG. 7 also shows the side interfacebetween first lattice portion 522 and second lattice portion 524.

Second surface 523 includes only a portion of second lattice portion524. As shown in FIG. 6, bottom surface of first lattice portion 522does not extend all the way to second surface 523. However, thishomogeneous surface may also provide a surface that is more readilycompatible or made compatible with the material of an adjacent layer.

FIG. 8 is an exploded view of a portion of lattice layer 522 shows theinterdigitation of first lattice portion 522 and second lattice portion524. First lattice portion 522 defines openings or pores 526 configuredto receive extensions of second lattice portion 524. Pores 526 have afirst height 548, which in some embodiments, is the same height as firstlattice portion 522. These extensions project away from an upper surface549 of second lattice portion 524 to a height shown by second height546. In some embodiments, such as those shown in the embodiments in thefigures, first height 548 and second height 546 are the same. In otherembodiments, first height 548 and second height 546 may be the same ordifferent. Because in some embodiments second lattice portion 524 formsthe entirety of lower surface of lattice layer 522, a second latticeportion height 550 may be greater than second height 546.

As shown by the dotted lines in FIG. 8, the extensions of second latticeportion 524 are shaped and sized to be fitted within pores 526 of firstlattice portion 522. In some embodiments, the lattice portions may beformed separately so that second lattice portion 524 is actually pressedor press-fitted into pores 526. In other manufacturing embodiments, suchas those described below, these layers are injection molded in the samemold, where second lattice portion 524 is molded into first latticeportion 522. Therefore, while discussed herein for the sake ofconceptualization as second lattice portion 524 as being fitted withinfirst lattice portion 522, the lattice portions may be considered to beinterdigitated or interlocked without regard to which portion may bepressed into another portion or whether the portions are co-molded sothat neither portion is actually physically pressed into the other.

While lattice layer 520 may be made of any material, such as athermoplastic material or a thermoset material, because of aparticularly suitable manufacturing technique that employs shutoffinjection molding, thermoplastic materials may be especially well suitedfor lattice layer 520. Suitable materials include an ionomer resin, ahighly neutralized polymer composition, a polyamide resin, a polyesterresin, and a polyurethane resin. In some embodiments, the materials arefoamed or are cellular in structure. Mixtures and alloys of thesematerials are also suitable, with additives and fillers included in therecipe to manipulate the properties of the materials, from hardness andspecific gravity to melt flow.

Suitable additives and fillers may include, for example, blowing andfoaming agents, optical brighteners, coloring agents, fluorescentagents, whitening agents, UV absorbers, light stabilizers, defoamingagents, processing aids, mica, talc, nanofillers, antioxidants,stabilizers, softening agents, fragrance components, plasticizers,impact modifiers, acid copolymer wax, surfactants. Suitable fillers mayalso include inorganic fillers, such as zinc oxide, titanium dioxide,tin oxide, calcium oxide, magnesium oxide, barium sulfate, zinc sulfate,calcium carbonate, zinc carbonate, barium carbonate, mica, talc, clay,silica, lead silicate. Suitable fillers may also include high specificgravity metal powder fillers, such as tungsten powder and molybdenumpowder. Suitable melt flow modifiers may include, for example, fattyacids and salts thereof, polyamides, polyesters, polyacrylates,polyurethanes, polyethers, polyureas, polyhydric alcohols, andcombinations thereof.

Lattice layer 520 is, in some embodiments, made using injection moldingtechniques. For example, a mold configured with a cavity shaped like thedesired golf ball layer may be provided and melt injected into thecavity via gates, which are very well known techniques. The precisemethods, such as the melt temperature and duration of injection may varydepending on the thermoplastic material involved. For example, inembodiments where highly neutralized polymers are used for makinglattice layer 520, during the injection molding process, the temperatureof the injection machine may be set within a range of about 190° C. toabout 220° C. For other melt materials, the temperature may be within oroutside of this range.

FIGS. 9-12 show one embodiment of an injection molding process thatforms the grid of the lattice layer, such as lattice layer 520, using atechnique known as shutoff molding. Shutoff molding generally usesmoving or members to form holes in a molded piece. This is accomplishedby closing the mold to move the members into a position to form a moldsurface for an initial injection, then retracting the member as the moldopens to leave a void in the molded piece. In some embodiments, thesemembers can telescope.

FIG. 9 shows a mold 600 configured to form a hemispherical cup-shapedlattice layer using telescoping members. Mold 600 includes a first moldportion 610 and a second mold portion 620. First mold portion 610includes a hemispherical cavity 612 having a smooth mold surface 614. Ifused to make a cover, mold surface 614 would not be smooth, but wouldinclude inverted dimples. Injection gates 618 are provided for theintroduction of melt into cavity 612. Any number of gates 618 may beprovided, even though only two are shown. A typical golf ball moldincludes 6-12 gates.

Second mold portion 620 includes a hemispherical second mold surface622. Second mold surface 622 defines openings 630 which are configuredto be the desired size and shape of the openings in the lattice layer,such as pores 526 of lattice layer 520.

Second mold portion 620 also includes at least one telescoping member625 positioned within an interior chamber 628. The same number oftelescoping members 625 as desired openings in the lattice layer areprovided. Telescoping members 625 are connected to an actuator 623,which is configured to extend and retract telescoping member 625. Thismay be accomplished using any method known in the art, such as pneumaticmethods, hydraulic methods, and servo motors. Actuator 623 is mountedwithin interior chamber 628 using any type of mount 626 known in theart. Actuator 623 may be controlled by the same controller (not shown)controlling the injection sequence.

Second mold surface includes a second mold surface 622 that defines theinner curved surface of the hemispherical cup. Second mold surface 622includes mold surface openings 630. Mold surface openings 630 areconfigured to accommodate the extension of telescoping members 625 intocavity 612.

FIG. 10 shows mold 600 in a closed position. Telescoping members 625 arein the retracted position, where the tips 624 of telescoping member 625are positioned within interior chamber 628.

FIG. 11 shows mold 600 with telescoping members 625 fully extended sothat tips 624 are in contact with first mold surface 614. Thus,telescoping member 625 form an additional set of mold surfaces to formholes in the resultant part.

To form the second lattice part, telescoping members 625 are retractedto the position shown in FIG. 10. Melt is introduced into the mold tofill the holes in the part formed during the injection as shown in FIG.11. The harder material is often injection molded first in standardshutoff molding systems, while the softer or higher flow rate materialis molded into and/or around the first material. Gates 618 may be usedif gates 618 are aligned with the holes in the part. Alternatively, andnot shown, additional gates may be provided in first mold portion 620 sothat melt flows through channels provided through interior chamber sothat melt flows into the hold through openings 630.

In sequence, the molding steps of this embodiment are generallyproviding a mold having a cavity, a mold surface, and telescopingmembers; positioning the telescoping members in an extended position, sothat the telescoping members are in contact with the mold surface;injecting a first material into the cavity; ceasing injecting the firstmaterial into the cavity; moving the telescoping members to a retractedposition; and injecting a second material into the cavity to produce alattice portion.

In other embodiments, the whichever portion of the lattice structure ismade from a harder or lower flow rate material, either the grid or thematerial that fills the grid pores, may be molded separately using anytechnique known in the art, such as injection molding, cutting,compression molding, or combinations of these methods. These hardelements may be pressed to the mold surface of a mold cavity, similar tohow telescoping member 625 are pressed to the mold surface. The secondmaterial, which is softer or has a high flow rate is then injected tosurround the hard material, thereby forming the lattice layer.

In some embodiments, telescoping members 625 may instead be fixedmembers, but are otherwise similarly configured as telescoping membersin that the fixed members are sized and shaped to form the openings inthe lattice layer and extend to surface 614. However, to form the secondportion of the lattice layer, i.e., to fill in the holes formed by thefirst shutoff molding process, a second mold portion 620 is removedafter the injection to form the first portion of lattice layer and athird mold portion replaces second mold portion. FIG. 12 shows a thirdmold portion 640 to replace second mold portion 620. Third mold portion640 includes a third mold surface 644 that defines the second surface ofthe lattice layer, such as second surface 523 of lattice layer 520.Third mold portion 640 includes additional gates 648 for injecting meltinto the mold.

As shown in FIG. 12, when closed, third mold portion 640 creates asecond mold gap 642 to accommodate the formation of the second latticeportion, such as second lattice portion 524. Second mold gap 642includes both the extensions and the base of the second lattice portion.Melt is introduced into second mold gap 642 through gates 648. When themelt fills second mold gap 642, the melt is shut off and the mold isopened. The lattice layer hemispherical cup is then removed from themold.

In sequence, the method of this embodiment is generally providing a moldhaving a cavity, a mold surface, and extended members; positioning theextended members in contact with the mold surface; injecting a firstmaterial into the cavity; ceasing injecting the first material into thecavity; removing extended members; providing a mold portion with asecond mold surface; and injecting a second material into the cavity toproduce a lattice portion.

After forming the hemispherical cups as shown in FIGS. 9-12, twohemispherical cups are joined together to form a completed latticelayer. If interior layers are provided, such as a core, the two cups areassembled around those layers and then joined. If exterior layers areprovided, such as a cover layer, the two cups are joined and then theexterior layers are molded onto the completed lattice layer. The cupsmay be joined using any method known in the art, such as with adhesives,welding, compression molding, or the like.

In some embodiments, the first portion of the lattice layer, forexample, the grid with pores or holes, is formed of a first material,such as by die cutting and compression molding, or by using injectionmolding with either the telescoping or fixed method shown above. Ahemispherical cup may be formed. The hemispherical cup may then beapplied to the outer surface of an inner layer, such as the smooth outersurface of a resin or rubber core. The holes or pores of the grid maythen be filled in by overmolding a second material using known injectionmolding techniques. An example of such an embodiment is shown in FIGS.13-19, which show a schematic embodiment of a method for making a golfball with interlocking layers including a combination of compression andinjection molding.

FIG. 13 shows a schematic embodiment of a system 700 for forming a grid.A cutting tool 710 configured to cut an initial portion of material 714into a grid 716 having at least one hole or pore 718. Grid 716 generallycorresponds to first lattice portion 522 shown in FIGS. 5-8 anddiscussed above. Portion 714 may be made of any type of materialtypically used in golf balls that is suitable for forming the gridportion of a lattice layer, such as thermoset materials such as rubberor thermoplastic materials such as various polymers and ionomers. Insome embodiments described herein, the material of portion 714 isanticipated to have a higher melt and glass transition point than thematerial used to fill pores 718, which material is discussed below.

The dimensions of portion 714 may be any dimensions suitable formanufacturing and/or inclusion in a lattice layer. For example, thelength and width of portion 714 may be any length or width suitable forfacilitating manufacturing, such as a continuous roll of material. Thelength and width of portion 714 may be cut down for subsequent moldingsteps. However, the thickness of portion 714 in most embodiments will beselected to be about the thickness of the resultant lattice layer.

In the embodiment shown in FIG. 13, cutting tool 710 is a die cut rollerhaving multiple cutting blades 712 configured into any desired pattern.In the embodiment shown in FIG. 13, this pattern is one of repeatingsquares. In other embodiments, the pattern may be different, but in mostembodiments will be a repeating pattern to form an even grid. In otherembodiments, cutting tool 710 may be any type of cutter capable ofcutting a pattern in a portion of material, such as a laser cuttingtool, an individual die cutter, a CNC machine with any of a variety ofcutting heads, or other machines or tools which may be apparent to thoseof skill in the art.

Cutting tool 710 may be arranged on a table, so that a technician orfactory worker positions portion 714 proximate cutting tool 710, or aconveyor system, which may move portion 714 towards cutting tool 710 ina more automated fashion. As indicated in FIG. 13, when a die cuttingroller is used, the roller rotates in the direction of the arrow toadvance portion 714 in a manufacturing direction. As portion 714 movesunderneath or proximate cutting tool 710, blades 712 remove sections ofmaterial from portion 714 so that grid 716 with pores 718 is formed.

Once grid 716 is formed, grid 716 may be sized, such as by cutting, tofit into a first mold 720, shown in FIG. 14. First mold 720 isconfigured to compression mold grid 716 into a hemispherical cup orsubstantially hemispherical cup. First mold 720 includes a first uppermold portion 722 and a first lower mold portion 724. First upper moldportion 722 includes a protrusion 726 which provides a first moldsurface. First lower mold portion 724 includes a cavity 728 whichprovides a second mold surface. The shape of protrusion 726 and cavity728 are complementary so that they fit together when first mold 720 isclosed. First upper mold portion 722 and first lower mold portion 724are configured to move together and move away from each other, usingtechniques well known in the art, so that protrusion 726 is insertedinto cavity 728 while trapping grid 716 between the two moldingsurfaces, as shown in FIG. 15. First mold 720 may apply both heat andpressure to conform grid 716 to the shape defined by protrusion 726 andcavity 728, in this embodiment, into hemispherical cups, such as firstcup 730 and second cup 731 shown in FIG. 16.

As shown in FIG. 15, pores 718 become distorted within first mold 720due to the compression molding process. It is possible to account forthis distortion using known techniques, such as those used in texturemapping or shrink wrap technologies, such as those described in U.S.Pat. No. 7,881,818, which is incorporated herein by reference. In someembodiments, such as those in which a regular grid is desired forhemispherical cups 731, blades 712 of cutting tool 710 will bepositioned in a non-regular pattern that will distort in first mold 720to the desired regular pattern. In other embodiments, where thedistortion is desirable or minimal, no accounting for the distortion maybe provided.

FIGS. 16 and 17 show the next step in the making of a golf ball with theassembly of two hemispherical cups, first cup 730 and second cup 731 andone interior golf ball component 732 into a gridded component 734.Interior golf ball component 732 may be any interior golf ball layer orcombination of interior golf ball layers, such as inner cores, outercores, single layer cores, cores and at least one intermediate layersuch as a mantle, and other combinations as will be readily apparent tothose in the art.

Interior golf ball component 732 is positioned between first cup 730 andsecond cup 731. Both first cup 730 and second cup 731 may be providedwith a lip to facilitate joining first cup 730 to second cup 731. Firstcup 730 and second cup 731 may be joined using any technique known inthe art, such as by a second compression welding step, adhesives, spinwelding, and combinations of these techniques. Joining first cup 730 andsecond cup 731 seals interior golf ball component 732 inside the cups.In most embodiments, interior component 732 is sized to fit snuglywithin the cups, such as touching all interior surfaces of the cups. Insome embodiments, adhesive, such as known adhesive films may be providedbetween interior component 732 and the grid to ensure that interiorcomponent 732 is inhibited from moving within the cups during play ofthe golf ball. In other embodiments, the joining method used to joinfirst cup 730 to second cup 731 adheres interior component 732 to thecups, such as by melting or bonding the material of the cups to thematerial of interior component 732.

FIG. 17 shows an assembled gridded component 734, where the griddedhemispherical cups are joined into a gridded sphere that containsinterior component 732. Gridded component 734 has empty pores 718.

To form the lattice layer, a second molding process is performed to fillpores 718 with a second material. In most embodiments, the secondmolding process is an injection molding process, one embodiment of whichis schematically shown in FIG. 18. In other embodiments, other moldingor filling processes may be used, such as compression molding, dipping,or the like.

In the embodiment shown in FIG. 18, a second mold 740 is provided.Second mold 740 includes second upper mold half 742 and second lowermold half 744, which are configured to move toward and away from eachother, as is well known in the art. Second upper mold half 742 includesa first injection cavity, which is defined by a first injection moldingsurface 743. Second lower mold half 744 includes a second injectioncavity which is defined by a second injection molding surface 745.Second upper mold half 742 includes at least one retractable pin 746configured to hold gridded component 734 away from first molding surface743 to create a gap between first molding surface 743 and griddedcomponent 734. Similarly, second lower mold half 744 includes at leastone retractable pin 748 configured to hold gridded component 734 awayfrom second molding surface 745 to create a gap between second moldingsurface 745 and gridded component 734. While three retractable pins areshown in each mold half in FIG. 18, any number of pins may be providedas desired for the process. The use of retractable pins, such as thecontrol and timing of retraction, are well known in the art.

To accommodate the introduction of melt into the mold, second upper moldhalf 742 includes a first injection molding gate 754 and a secondinjection molding gate 756. Similarly, second lower mold half 744includes a third injection molding gate 750 and a fourth injectionmolding gate 752. While four injection molding gates are provided inmold 740, any number of gates may be provided. In many golf ballinjection molds, between six (6) and twelve (12) gates are provided. Thegates are configured to receive a second molten material from aninjection molding system 760, which may be extruded with screws througha nozzle in fluid communication with the gates of second mold 740.

As the molten material or melt flows into second mold 740, the meltfills pores 718 (shown in FIG. 17) and the space between griddedcomponent 734 and first mold surface 743 and second mold surface to forman outer layer 760. Outer layer 760 forms the second lattice portion ofthe lattice layer by filling pores 718 and forms a smooth outer surfaceof the lattice layer component, shown in FIG. 19. Outer layer 760 ispeeled away to show interior component 732, grid 716, and how outerlayer 760 is interdigitated with grid 716. If formed as a cover, such asof a durable cover material and with dimples, the component shown inFIG. 19 may be a completed golf ball. In other embodiments, a coverlayer and/or one or more additional layers may subsequently be moldedonto the component shown in FIG. 19 to form the complete golf ball.

The material for outer layer 760 may be any material known in the artthat is suitable for injection molding, such as thermoplastic materialsand certain thermoset materials capable of being injected by processessuch as RIM molding. In some embodiments, the material for outer layer760 has a lower melt and glass transition temperature than the gridmaterial so as not to deform or change the materials properties of thegrid during the second molding process. In other embodiments,deformation or changing the materials properties of the grid will not bea concern.

While various embodiments of the invention have been described, thedescription is intended to be exemplary, rather than limiting and itwill be apparent to those of ordinary skill in the art that many moreembodiments and implementations are possible that are within the scopeof the invention. Accordingly, the invention is not to be restrictedexcept in light of the attached claims and their equivalents. Further,any element of any embodiment may be substituted into any otherembodiment unless specifically restricted in the specification.Similarly, the sequence of any method described herein is not limited tothe order in which that method is presented unless specificallyrestricted in the specification. Also, various modifications and changesmay be made within the scope of the attached claims.

1-5. (canceled)
 6. A method of making a golf ball comprising the stepsof: making a core; making a grid formed as a sheet from a firstmaterial, the grid having at least one pore; forming the grid into acup; positioning the cup on the core; and overmolding a second materialonto the grid, so that the second material at least partially fills theat least one pore of the grid.
 7. The method of claim 6, wherein thestep of making the grid comprises cutting the first material.
 8. Themethod of claim 7, wherein the step of making the grid comprises diecutting the first material.
 9. The method of claim 6, wherein the stepof forming the grid comprises compression molding the grid.
 10. Themethod of claim 6 further comprising the step of cutting the grid priorto forming the grid into a cup.
 11. The method of claim 6 furthercomprising the step of adhering the cup to the core.
 12. The method ofclaim 6 further comprising the step of forming at least one additionallayer on the core prior to positioning the cup on the core.
 13. Themethod of claim 12 further comprising the step of adhering the cup tothe at least one additional layer.
 14. The method of claim 6, whereinthe step of overmolding the second material comprises injection moldingthe second material onto the grid.
 15. The method of claim 6 furthercomprising forming a second cup from a second grid.
 16. The method ofclaim 15, wherein the cup and second cup are joined together toencompass the core. 17-20. (canceled)
 21. The method of claim 6, whereinthe step of forming the grid comprises injection molding the grid. 22.The method of claim 21, wherein the injection molding step comprisesshut off molding.
 23. A method of making a golf ball comprising thesteps of: making a core; making a grid by injecting a first materialinto a mold using a shutoff molding technique to form a grid, whereinthe grid has at least one pore, wherein the mold has a hemisphericalcavity so that the grid is formed as a hemispherical cup, and whereinthe at least one pore is formed by the shut-off moldinq technique bymoving at least one member into the hemispherical cavity while the moldis closed and then retracting the member while the mold is opened; andovermolding a second material onto the grid, so that the second materialat least partially fills the at least one pore of the grid.
 24. Themethod of claim 23, wherein the step of overmolding the second materialoccurs in the mold.
 25. The method of claim 24 further comprising thestep of positioning the core within the mold prior to the step ofovermolding the second material.
 26. The method of claim 23 furthercomprising the step of positioning the hemispherical cup on the core.27. The method of claim 26, wherein the step of overmolding the secondmaterial occurs after the step of positioning the hemispherical cup onthe core.
 28. The method of claim 23 further comprising the step offorming at least one additional layer on the core prior to positioningthe hemispherical cup on the core.
 29. The method of claim 23 furthercomprising the steps of forming a second grid, wherein the second gridhas at least one pore; positioning the first grid and the second gridonto the core so that the first grid and the second grid togethersubstantially surround the core; and joining a perimeter of the firstgrid to the second grid.